RFC 9839: Navigating the Perils of Problematic Unicode Characters

This Tech article discusses the dangers lurking within the Unicode character set, focusing on RFC 9839. This RFC identifies problematic Unicode characters that can cause issues in software and network protocols, proposing three safer subsets. A JSON username example illustrates the potential problems these characters create. The author compares RFC 9839 to the more comprehensive PRECIS standard and recommends a Go library for validation.